Analysis design and modeling of crescent antenna for UWB applications

A crescent-shaped planar monopole antenna for UWB applications is proposed. The design parameters were investigated using CST software package. Modeling of the UWB monopole antennas is investigated using two methods. The input impedance is represented by the first Foster canonical form, where the equivalent circuit components at resonance are derived from either the reflection coefficient or the input impedance responses of the investigated antenna. In the second method, a SPICE-compatible equivalent circuit is used to model the input admittance of the antenna utilizing the vector fitting technique. The CST Microwave Studio is used to obtain the reflection coefficient and input impedance of the investigated antenna, and these results are used to extract values of the components of the equivalent circuit. The performances of the investigated methods are compared, and validity of the modeling methods is verified using MATLAB and ADS softwares.